O-ethyl s-(ethylxanthoyl) n, n-diethylamidothiophosphate



" UNITED STATES ?A.TENT OFFICE O-ETHYL S- (ETHYLXANTHOYL) N,N-DI-ETHYLAMIDOTHIOPHOSPHATE Henry Tolkmith, Midland, Mich., assignor to TheDow Chemical Company, Midland, Mich., a corporation of Delaware NoDrawing. Application April 21, 1953, Serial No. 350,244

1 Claim. 1 This invention is directed to the O-ethyl S- (ethylxanthoyl)N,N-diethylamidothiophosphate of the formula 2 perature of from 40 to 80C. Upon completion of the reaction, the mixture may be filtered and thefiltrate concentrated by distillation under reduced pressure to atemperature up to 80 C.

1 5 to obtain as a residu S-(ethylxanthoyl) N ,N-diethylamidothiophosphoric chloride. This com P-N pound is an oilyliquid having a density of 1.195

OZHFO/ \CQHS at 18 C. The latter compound and the described Thiscompound is a viscous oil, somewhat solumethod for its productionconstitute the subject F ble in many organic solvents and substantially10 5 3553, iggg senal med insoluble in water. It is of value as anintermediate for the preparation of more complex i fi g' z g preparatlonan alcoholic H Q grams (0.1 mole) of SOdlllll'l organic derivatives andas a bOXlC constituent o1 ethylalte in 32 milliliters of etha nol wasadded paiasltlclde compositions. with Stirring to 27 5 I grams (0.1mole) of S- Thls new compound may be prepared by 1e- (ethylxanthoyl) N,Ndiethylamidothlophosacting an alkali metal ethylate with S--(ethylphoricchloride dissolved. 125 xanthoyl) N ,N-diethylamidothioph.osphoricchlom1 Item of ride of the formul zene and the resulting mlxture heatedfor 2 hours at the boiling temperature and under reflux. The 02115 crudereaction mixture was then filtered and 1 H the filtrate concentrated bydistillation under reduced pressure at gradually increasing temperaturesup to 80 C. to obtain as a residue an O- 01 ethyl S-(ethylxanthoyl)N,N-diethylamidothioin an inert organic solvent such as benzene. Ofphosphate product. The latter is a viscous oil the alkali metalethylates found useful in the rehaving a d sity of 1.054 at 20 C.action, it is preferred to employ the sodium com- The new o-e yls-(ethylx nth yl) N,N-dipound. In practice, good results are obtainedethylamidothiophosphate product s e ective as when substantiallyequimolecular proportions of & parasiticide a d p to be p y for thereactants are employed. the control of a wide range of agricultural andIn carrying out the reaction, the sodium ethylhousehold pests such asflies, mites, aphid ate is added with stirring to the S-(ethylxanbeetlesand cockroaches. For such use, the comthoyl) N,N-diethylamidothiophosphoric chloride p und may be dispersed on an inertfinely divided dispersed in the solvent and the resulting mix- Solid andp y as a dust. Such ur S ture heated for a period of time at atemperature may be dispersed in Wat r With the aid of a disof from to 80c. Temperatures substanp rs s n W t n nt n th r sultin tially in excessof 80 C. for any appreciable q s Suspensions p y a D W In period of timeare to be avoided, as the desired other procedur s, t e ew p Od lCt aybe emproduct has a tendency to decompose at such ployed in oils, as aconstituent in oil-in-water temperature. If desired, an alcoholicsolution of 40 emulsions, or in water dispersion with or without theethylate may be employed as a starting mathe addition of emulsifying,wetting or dispersing terial. It has been found that the excess alcoholagents. Suitable concentrations of the toxicant does not interfere withthe course of the reaction. in dusts are in the order of from about 0.1to 10 Upon completion of the reaction, the mixture pe cent by W t of tdust and in liquid may be filtered and the filtrate concentrated bypensions from about 0.1 to 3 pounds p 100 distillation under reducedpressure at gradually 5 0 e p y Xtu e. I11 representative increasingtemperatures up to a temperature of operations ag st Z-SDOtted Spidermites, 100 80 C. to separate low boiling constituents and to percentkills of this organism are obtained with obtain as a residue the desiredproduct. aqu us sp ay p s s containing 1.5 p u ds The S-(ethylxanthoyl)N,N-diethylamido- 0f the toxic thiophosphate per 100 gallons ofthiophosphoric chloride employed as a starting material in theabove-described method may be prepared by reacting one molecularproportion of sodium ethylxanthate with one molecular proportion ofdiethylamidophosphoric dichloride in an inert organic solvent such asbenzene. In carrying out the reaction, the reactants and solvent aremixed together and the resulting dispersion heated for a period of timeat a temthiophosphate.

spray mixture.

This is a continuation in part of my copending application Serial No.203,775, filed December 30, 1950.

I claim:

O-ethyl S-(ethylxanthoyl) N,N-diethylaniido- HENRY TOLKIVEELTH. Noreferences cited.

